Stationary induction apparatus



Nov. 21, 1939. R. F. KNEISLEY STATIONARY INDUCTION APPARATUS Filed Sept. 23, 1937 Kai Patented Nov. 21, 1939 V UNITED STATES PATENT OFFICE STATIONARY INDUCTION APPARATUS Richard F. Knelsley, Toledo, Ohio Application September 23,1937, Serial No. 165,379 '3 Claims. (c1. lul -11c) This invention relates to stationary induction vention, and Fig.4 is a view of a modified form apparatus, and is more particularly directed to of leak unit. high reactance, shell type, transformers. Referring to the drawing, the invention is The invention is particularly used in connecshownin connection with a transformer having a 5 tion with a shell type ,transformer in which it is primary winding l and a secondary winding 2 5 desired to introduce additional magnetic circuits disposed about a center core of laminated mag- 1 so as toincrease the internal reactance of the netic material 3 and within the confines of a transformer. It is freguently desirable to add built up magnetic shell 4. The laminations of magnetic leakage paths between the primary and the shell! are held in place by upper and lower 1 secondary windings to increase the reactance of a retaining members 5 and 6 which are fastened 10 the transformer to such a value as will insure together byflsuitable bolts 8.. As in the usual its protection from the flow of abnormally high practice, wooden wedges 9 are used to tighten current to short circuits, or other conditions the primary and secondary coils on the core 3. which might increase thefiow of an abnormally In a transformer of this type, it is frequently high value. l 7 desirable to provide an additional magnetic path 15 The provision of additional magnetic. paths newhich is really a leakage path or shunt since the cessitates the insertion of laminated stacks of flux from the primary is permitted to flow withmagnetic material between the core. and shell out linking a secondary coil. For this purpose, of the transformer and between the primary and laminations a introduced tw e the e secondary coils. It has been found in practice and core 3 at a point between the primary and 20 that stacks of laminations of this character may secondary coils. 1 r i be assembled so as to be relatively noiseless for The leakage, or shunt, paths in accordance a short period of time, but after the transformer with the present invention include units In which has been time and becomes heated and cooled are made up of stacks of magnetic material in through several cycles, these laminations work the form of thin laminations which aremolded 25 v loose and themagnetic-stress to which they are as a unit by completely embedding them in a subjected causes them to hum and make the covering I 2 which is preferably} of relatively transformer objectionably noisy. yieldable rubber, or other material having similar Ithas also been found that in mosttranscharacteristics. The magnetic leak units I0 formers, it is necessary to assemble the laminamay be made in any suitable manner, although 30 tions with some type offastening means to hold a simple method is to place the C stack of prethem in place relative to the remaining, transviously cut laminations H in a mold, spaced from former parts. Fastening elements which pierce the bottom'and sides thereof and fill themold the laminations cause eddy currents to be set with rubber.

up therein and increase the operating .tempera- The leakunits may be placed in the trans- 35 ture, at least locally, of the transformer. Furf m duri the assembly Operation, dwh n ther, such fastening elements are relatively exthe shell 4 is fixed inits final position, it is forced pensive if made of proper material andif propinto biting engagement with the leak units which erly constructed and assembled V in turn are forced tightly against thecore 3.

40 The primary object of the present invention ince the covering of the leak units possesses con- 40 is the provision of a device to provide additional i bki inherent y, n0 Ot e s en magnetic paths in a transformer, constructed in elements are required hold the units i P ace h a mann that it will r main n is les relative to the shell and core of the transformer. throughout its entire life and may be held in e resiliency Of t ng surrounding the place in a transformer preferablywithout the leak laminations provides,'in additioma con'tinuuse of extraneous fastening elements. ous gripping tension. holding the laminations Other objects and advantages of the invention together, and thus dampens the vibrations of will become apparent as the description proceeds, t e laminat ons which are caused by the changreference being had 'to-the accompanying drawing magnetic flux. This eliminates noise or hum ing, in which V which such vibrations would otherwise produce. 5

Figure l is a plan view of a transformer em- If desired, the units may be previously formed bodying the present invention; Fig.2 is'a section to a configuration such as shown in Fig. 4 and on line 2-4 of Fig. 1; Fig. 3 is a perspective introduced into the transformer after assembly view, with parts broken away, of a magnetic leak and held therein by reason of the rubber coverconstructed in accordance with the present ining engaging the stacks of laminations which form the principal magnetic paths in the transformer. In this form the unit may be provided with a head part I! slightly larger than the remainder of the body. The unit may thus be forced between the core and shell until the head I2 rests on the adjacent metallic parts.

While the invention has been described in connection with a transformer of a particular type and construction, it should be appreciated that it is adaptable to any type transformer in which shunt paths are used to increase the reactance. Such adaptation will undoubtedly require a change in configuration of the leak unit.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent, is:

1. A stationary induction apparatus including a magnetizable shell and a core member therewithin and spaced therefrom, inductively related windings embracing said core, and a magnetizable shunt between said core and shell, said shunt including a body having magnetizable laminations, and a resilient covering, said covering being of a strength and its resilience of a degree whereby to hold the, laminations against vibrations, the overall width of said covered shunt being greater than the distance between the core and shell whereby upon compression to hold the shunt firmly in position.

2. A stationary induction apparatus including a magnetlzable shell and a core therewithin and spaced therefrom, inductively relatedwindings embracing the core, a magnetizable shunt held shunt in position by and upon compression shunts, the overall width of said covered shunts the shunts together so as to hold the laminations against vibration.

RICHARD F; KNEISLEY'. g 

